Shares of Union Pacific Corporation (NYSE:UNP) were slammed on earnings Thursday. The transportation company under-performing expectations, which were sky high. As the stock falls, there is a significant buying level at $123.50. This will be a key technical retrace level of support and should give the stock a significant bounce. Granted, the stock is still far away from this level, but that means it has much more downside until it is worth buying. Be patient and be ready to pounce when the chart says 'buy'.